1. Field of the Invention
This invention relates to an apparatus and a method of producing a harness in which a distinctive mark is applied to an outer periphery of an electrical cable.
2. Statement of the Prior Art
There are many kinds of harness to be mounted on an automobile or the like. A distinctive mark is applied on an outer periphery of each electrical cable in order to easily distinguish a cable kind in each harness.
A prior apparatus for producing a harness on which the distinctive mark is applied will be described below by referring to FIGS. 13 to 18 for convenience of explanation.
FIG. 13 is a plan view of a prior harness producing apparatus. FIG. 14 is a side view of the prior harness producing apparatus. FIG. 15 is a side view of the prior harness producing apparatus illustrating another state. FIG. 16 is a side view of the prior harness producing apparatus illustrating still another state.
A harness producing apparatus A1 disclosed in Japanese Patent Public Disclosure No. 80-151906 is illustrated in FIGS. 13 to 16.
The harness producing apparatus A1 comprises a cable feeding mechanism 20 having two feeding rollers 11, a pair of draw rollers 12a, a front side clamp 12, a cutter mechanism 13 having a plurality of cutters 13a and 13b, a rear side clamp 14, two terminal press-attaching mechanisms 21a and 21b disposed on the opposite sides of the cutter mechanism 13, and two marking mechanisms 22a and 22b disposed adjacent to the press-attaching mechanisms 21a and 21b. An electrical cable 10 is passed along a predetermined cable pass line in the apparatus A1.
Both clamps 12 and 14 hold the cable 10 and the cutters 13a, 13b of the cutter mechanism 13 operates in synchronization with the clamps 12 and 14. Then, a middle cutter 13a in the cutter mechanism 13 cuts off the cable 10 and opposite side cutters 13b cut into sheaths of the cables. While maintaining this state, the front side clamp 12 moves in a direction shown by an arrow Q so that the cable 10 held by the clamp 12 (hereinafter referred to as "residual cable" 10) moves in the direction Q, thereby stripping the sheath from an end of the residual cable 10. At the same time, the rear side clamp 14 moves in a direction shown by an arrow P so that the cable 10 held by the clamp 14 (hereinafter referred to as "cut cable" 10) is stripped of its sheath at one end.
Then, The residual cable 10 together with the front side clamp 12 move in a direction shown by an arrow R in FIG. 13, a terminal 2 (FIG. 1B) is press-attached to a stripped end of the residual cable 10 by a terminal press-attaching mechanism 21a, a distinctive mark is applied to the residual cable 10 near the stripped end thereof by the marking mechanism 22a, and the front side clamp 12 returns to its original position.
On the other hand, the cut cable 10 together with the rear side clamp 14 move in a direction shown by an arrow S in FIG. 1, a terminal (not shown) is press-attached to a stripped end of the cut cable 10 by a terminal press-attaching mechanism 21b, the distinctive mark is applied to the cut cable 10 near the stripped end thereof by the marking mechanism 22b, the cut cable 10 is discharged to a given discharging position, and the clamp 14 returns to the original position.
Then, after both clamps 12 and 14 release the cable, two feeding rollers 11 are rotated and the electrical cable 10 is fed toward the draw rollers 12a. At a little time lag after feeding the cable, the draw rollers rotate so that the sheathed cable 10 is fed to the rear side clamp 14.
Thereafter, the above steps are repeated to produce the cut cable (harness) which is provided with the terminals 2 on the opposite stripped ends thereof and the distinctive mark on the given area.
However, since the indicative mark is applied to the cable simultaneously with a terminal press-attaching process, namely a cable end treating process after cutting the cable in the harness producing apparatus A1, it is necessary to further dispose the marking mechanisms 22a and 22b on a cable end treating section on which the front side clamp 12, cutter mechanism 13, rear side clamp 14, terminal press-attaching mechanisms 21a and 21b and the like have a complicated arrangement, thus making the construction intricate.
In order to eliminate the above problem, Japanese Patent Public Disclosure No. 64-48319 (1989) discloses an apparatus which applies an indicative mark to an electrical cable prior to cutting it.
In another prior harness producing apparatus A2 shown in FIG. 16, the marking mechanism 30 is disposed on an upstream from the cable feeding mechanism 20 in a cable Feeding direction P. The marking mechanism 30 is provided with a pair of feeding rollers 31 adapted to clamp the cable 10 and a pair of marking heads 32 adapted to contact with the outer periphery of the cable 10. Further, a cable storage mechanism 40 is arranged between the cable feeding mechanism 20 and the marking mechanism 30 in order to receive the cable 10 therebetween.
In the harness producing apparatus A2, the cable 10 is intermittently fed in the direction P by clamping and driving the cable 10 by the feeding rollers 31 in the marking mechanism 30. The marking heads 32 press the cable during a feed resting period so that the distinctive mark 5 is applied to the cable 10 at a given outer face thereof.
On the other hand, the feeding rollers 11 of the cable feeding mechanism 20 feed the cable 10 intermittently in the same manner, the cutter mechanism 13 cut the cable 10, and the cable end treating processes such as end sheath stripping, terminal press-attaching and the like are carried out.
Since the distinctive mark is applied to the cable prior to cutting it in the harness producing apparatus A2, it is not necessary to dispose the marking mechanism 30 in the cable end treating section near the cutter mechanism 13 in which many elements are arranged complicatedly. Accordingly, the apparatus A2 does not bring about a problem of complication in construction.
However, since the feeding rollers 31 of the marking mechanism 30 feed the cable intermittently in the apparatus A2 while the feeding rollers 11 of the cable feeding mechanism 20 feed the cable intermittently independent upon the feeding rollers 31, a gap between a cutting position of the cable 10 and a marking position of the cable is caused due to feed errors between both rollers 11 and 31 upon operation of the apparatus for a long time. Consequently, it is impossible to precisely apply the distinctive mark to a given area on the harness 1.